<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      const obj = {
        age: 20,
        toString() {
          return this.age;
        },
        // valueOf() {
        //   // console.log("valveOf");
        //   return 200;
        // },
      };
      console.log("Number(obj)", Number(obj));
      console.log("String(obj)", String(obj));
      console.log("obj + 100", obj + 100);
      console.log("+obj", +obj);
      console.log("obj - 20", obj - 20);
    </script>
  </body>
</html>
